The present disclosure relates to a centrifugal pump, and more particularly to an output nozzle which provides stable Head vs. Flow performance at shut-off.
Most centrifugal pumps have a Head vs. Flow curve that tends to flatten out or droop at low flows. This effect becomes more pronounced at shut-off or zero-flow and results in an unstable curve.
Unstable, i.e. droopy or flat, Head vs. Flow performance may complicate operation as slight changes in system resistance may result in large flow variations and/or cause the pump equipment to operate at an unacceptable flow point.